SIMBAD (Set of Identificati=
ons,
Measurements, and Bibliography for Astronomical Data) can be accessed from
the WWW (at the CDS -
http://cdsweb.u-strasbg.fr/Simbad.html
or at the CfA -
http://cfa-www.harvard.edu/simbad),
via telnet or e-mail. SIMBAD has 5,000 individual user accounts in 55
countries.
An IP control password is available which allows institutional access to
the service. As it is necessary to have an account, prospective users in
the US (charges are assumed by NASA) should send a request to
simbad@cfa.harvard.edu.
Others (European charges are covered by ESO and ESA) should enquire at
their libraries or question@simbad.u-strasbg.fr.

SIMBAD contains more
than 1.5M objects, more than 4.3M identifiers and more than 95k references
from 90 journals (since 1950 for stars and since 1983 for extragalactic
objects). The data included in SIMBAD evolves constantly as the measurements
are updated and more references included daily (in 1994 there were 500
new entries per month).

Its most important characteristic
is the cross-identification of objects. SIMBAD contains a cross-index to
several hundred astronomical catalogs and logs of space observatories.

It can be queried by
name, coordinates or reference code. SIMBAD is the result of a cooperative
effort among several institutions. The bibliography is compiled by the
Institute d'Astrophysique in Paris and the Bordeaux Observatory; the catalogs
by the Observatoire du Midi Pyrenées, the Paris and Besançon
Observatories, Astronomisches Recehen-Institut (Heidel berg) and Institute
for Astronomy of the Russian Academy of Sciences; correction to the databases
are made by the Montpellier Observatory.

As was the case with
NED, SIMBAD can also be used in a client/server mode to retrieve essential
information on objects to be included in other programs.